US8438914B2 - Apparatus for measuring the unconfined yield strength and time unconfined yield strength of bulk granular material - Google Patents
Apparatus for measuring the unconfined yield strength and time unconfined yield strength of bulk granular material Download PDFInfo
- Publication number
- US8438914B2 US8438914B2 US12/945,840 US94584010A US8438914B2 US 8438914 B2 US8438914 B2 US 8438914B2 US 94584010 A US94584010 A US 94584010A US 8438914 B2 US8438914 B2 US 8438914B2
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- yield strength
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- 239000008187 granular material Substances 0.000 title claims abstract description 9
- 239000000843 powder Substances 0.000 claims abstract description 7
- 238000003825 pressing Methods 0.000 claims abstract description 4
- 239000000523 sample Substances 0.000 claims 16
- 239000013590 bulk material Substances 0.000 abstract description 5
- 239000000463 material Substances 0.000 abstract description 3
- 230000006835 compression Effects 0.000 description 8
- 238000007906 compression Methods 0.000 description 8
- 125000006850 spacer group Chemical group 0.000 description 3
- 230000007613 environmental effect Effects 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 101100327917 Caenorhabditis elegans chup-1 gene Proteins 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- 238000005056 compaction Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N3/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N3/08—Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N2203/00—Investigating strength properties of solid materials by application of mechanical stress
- G01N2203/02—Details not specific for a particular testing method
- G01N2203/026—Specifications of the specimen
- G01N2203/0284—Bulk material, e.g. powders
Definitions
- This invention relates to an apparatus for measuring the unconfined yield strength of bulk granular materials and how it changes over time under different environmental conditions.
- the information produced by these measurements can determine how well a powder performs in various processes and equipment such as pharmaceutical tableting machines, pneumatics conveyors, container filling machines, drying systems, and catalyst towers.
- a typical apparatus for measuring unconfined yield strength is disclosed by Michael Rock and Jorg Schwedes in Powder Volume 157, June 2005.
- bulk material is compressed in a cylindrical mold that has been divided into two halves. During the compression, the two halves are held together by ring bands. After compression, the mold is removed and the freestanding material is broken by applying for to its top area.
- the main disadvantage of this approach is that sides of the mold must be manually removed to free the sample for the break test.
- the bottom of the mold must be blocked with a plug or flat plate to ensure sample does to flow from the bottom of the mold.
- U.S. Pat. No. 5,289,728 Another apparatus for measuring unconfined yield strength is disclosed in U.S. Pat. No. 5,289,728.
- a sample of bulk material is compressed in a cylindrical mold with an opening at the bottom. During compression, the opening is blocked by a plug. After the sample has been compressed, the plug is removed and the sample is pushed through the bottom opening by pressure from above. The force required to push the sample from the mold is related to its unconfined yield strength.
- the disadvantage of this approach is that is expensive to automate and does not directly measure the unconfined yield strength of the sample.
- the inventors of the present invention determined that industry and academia needed a simple, easy to understand, and inexpensive apparatus to measure the unconfined yield strength.
- the apparatus also needed to have inexpensive test cells so that many samples could be prepared and put under pressure for various lengths of time and under different environmental conditions.
- the heart of the invention is a test cell made up of a sample cup with a hole or holes in the bottom smaller than the internal dimensions of the cup. Fitting into the cup is a base that covers the bottom of the cup and hole(s).
- the cup can have inner walls perpendicular to the horizontal axis of the cup or angled walls so that the inner dimensions of the cup become smaller as the depth in the cup increases.
- the bulk granular material to be tested is then poured into the cup on top of the base and the cup is filled. After filling, a lid is placed on the cup and pressure is applied to compress the sample. This pressure is applied mechanically or with weights over a predetermined time period.
- the compressed sample is removed from the sample cup by pushing the sample out of the cup from below through the bottom hole(s).
- the sample is then broken to determine the unconfined yield strength of the sample by applying pressure to the sample cup lid on top of the sample.
- FIG. 1 presents a drawing of the preferred embodiment of the sample cup.
- FIG. 2 presents a drawing of the preferred embodiment of the apparatus configured to apply pressure to the sample to compress it.
- FIG. 3 presents a drawing of the preferred embodiment of the apparatus configured to remove the sample from the test cup and break it.
- FIG. 4 presents a drawing of the preferred embodiment of the sample cup with consolidating pressure applied by weights.
- FIG. 5 presents an alternative embodiment of the sample cup with internal side walls at an angle relative to the vertical axis of the cup.
- the preferred embodiment of the invention is shown in FIGS. 2 and 3 .
- the test cell made up of a sample cup with a hole or holes in the bottom smaller than the internal dimensions of the cup.
- the preferred sample cup 1 is illustrated in FIGS. 1 , 2 and 3 and is cylindrical with a round hole 4 in its center roughly one quarter of inner diameter of the cup.
- Fitting into the cup is a base that covers the bottom of the cup and hole(s).
- the base 2 is a flat disc with dimensions just smaller than the inner diameter of the cup to allow free movement.
- the bulk material to be tested is then poured into the cup on top of the base and the cup is filled. After filling a lid is placed on the cup and pressure is applied to compress the sample.
- pressure is applied to the sample lid 3 by lifting the sample cup on an external base 5 from below by a shaft 6 driven by a stepper motor driven screw 7 into a spacer 8 in contact with a force transducer 9 .
- the compressed sample is removed from the sample cup by pushing the sample out of the cup from below through the bottom hole(s).
- the external base 5 is removed from below the cell and a break cap 10 is put on top of the sample cup.
- the break cap has a notch for the sample cup and keeps the sample cup in place while the shaft 6 moves up and lifts the sample out of the cup through the hole 4 in the sample cup.
- the sample is then broken by applying pressure to the cup lid sitting on the sample.
- shaft 6 continues to lift the sample and push the cup lid 3 into the force transducer 9 until the pressure on the lid breaks the sample. The maximum pressure is recorded and used to calculate the unconfined yield strength.
- a weight spacer and weights are placed on the sample cup lid to apply the compression pressure to the sample.
- a cylindrical weight spacer 11 and cylindrical weights 12 are placed on the sample cup lid 3 to apply pressure to the sample.
- the sample cup with sample and weights can then sit for hours or days under controlled conditions to time consolidate the sample.
- the sample is then removed from the sample cup and broken to measure the change in unconfined yield strength over time.
- the internal sides of the sample cup are not perpendicular to the horizontal axis of the cup but rather are angled relative to the horizontal axis so that the inner dimensions of the sample cup become smaller as the depth of the cup increases. This greatly reduces the distance that the sample must to travel before it loses contact with the side walls of the sample cup. This reduces the chances of the sample being effected by the friction at the walls of the sample cup while it is being lifted from the sample cup.
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- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
Description
Claims (3)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US12/945,840 US8438914B2 (en) | 2010-11-13 | 2010-11-13 | Apparatus for measuring the unconfined yield strength and time unconfined yield strength of bulk granular material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US12/945,840 US8438914B2 (en) | 2010-11-13 | 2010-11-13 | Apparatus for measuring the unconfined yield strength and time unconfined yield strength of bulk granular material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| US20120118072A1 US20120118072A1 (en) | 2012-05-17 |
| US8438914B2 true US8438914B2 (en) | 2013-05-14 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US12/945,840 Active 2031-08-23 US8438914B2 (en) | 2010-11-13 | 2010-11-13 | Apparatus for measuring the unconfined yield strength and time unconfined yield strength of bulk granular material |
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| US (1) | US8438914B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10690649B2 (en) * | 2017-12-28 | 2020-06-23 | Taiyuan University Of Technology | Supercritical CO2 reactor and test system of creepage, diffusion and erosion of rock mass |
| US10712253B2 (en) * | 2017-12-15 | 2020-07-14 | Northwest Institute Of Eco-Environment And Resources, Chinese Academy Of Sciences | Simulation device for interaction between deep reservoir rock and fluid in basin and method for using same |
| US11047789B2 (en) * | 2019-08-02 | 2021-06-29 | Southwest Petroleum University | Irregular rock sample high-pressure permeation device with adjustable flow direction and test method thereof |
| US11156538B2 (en) * | 2018-12-18 | 2021-10-26 | Gregory Peter Martiska | Rheometer for measuring the flow properties of powders and granular materials |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8875591B1 (en) * | 2011-01-27 | 2014-11-04 | Us Synthetic Corporation | Methods for measuring at least one rheological property of diamond particles |
| CN104034595B (en) * | 2014-05-28 | 2016-07-06 | 中国建筑股份有限公司 | Fresh mortar slurry is without the determinator of lateral spacing bearing capacity and assay method |
| CN104990755B (en) * | 2015-08-11 | 2017-09-19 | 上海中船三井造船柴油机有限公司 | A kind of pressure test device and method for lifting tool |
| CN108871962B (en) * | 2018-04-24 | 2021-08-24 | 上海大学 | Unconfined compressive test device for soil samples with controllable suction |
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2010
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| US3116633A (en) * | 1962-06-15 | 1964-01-07 | Wilson Nuttall Raimond Enginee | Instrument for measuring shearing stress-normal stress relationships of soils |
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| US3478572A (en) * | 1968-07-12 | 1969-11-18 | John L Mcrae | Wall friction device |
| US3616685A (en) * | 1970-06-29 | 1971-11-02 | Dames And Moore | Load applying device for a pressure test chamber |
| US3820385A (en) * | 1973-01-16 | 1974-06-28 | Inst Ingenieria | Chamber for testing soils with triaxial stresses |
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| US3998090A (en) * | 1975-11-07 | 1976-12-21 | The United States Of America As Represented By The Secretary Of The Army | Soil compactor |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US10712253B2 (en) * | 2017-12-15 | 2020-07-14 | Northwest Institute Of Eco-Environment And Resources, Chinese Academy Of Sciences | Simulation device for interaction between deep reservoir rock and fluid in basin and method for using same |
| US10690649B2 (en) * | 2017-12-28 | 2020-06-23 | Taiyuan University Of Technology | Supercritical CO2 reactor and test system of creepage, diffusion and erosion of rock mass |
| US11156538B2 (en) * | 2018-12-18 | 2021-10-26 | Gregory Peter Martiska | Rheometer for measuring the flow properties of powders and granular materials |
| US11047789B2 (en) * | 2019-08-02 | 2021-06-29 | Southwest Petroleum University | Irregular rock sample high-pressure permeation device with adjustable flow direction and test method thereof |
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| Publication number | Publication date |
|---|---|
| US20120118072A1 (en) | 2012-05-17 |
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